Chronic injections of the Beta-adrenergic agonist, isoproterenol, cause several biochemical alterations in protein biosynthesis of the rat parotid gland. Included in these changes are an alteration in the carbohydrate structure of 200kd salivary glycoprotein synthesized in the normal rat parotid, resulting after isoproterenol treatment in the production of the second glycoprotein of 220kd. Furthermore the 200kd glycoprotein has been shown to act as an acceptor substrate in the reaction UDPgal[14C] + glcNAc - UDP + gal[14C]-galNAc which is catalyzed by the enzyme UDPgalactose:N-acetylglucosamine galactosyltransferase. This 4 Beta-galactosyltransferase has previously been shown to increase 6-10 fold in rat parotid glands treated with isoproterenol, while another enzyme 3 Beta-N-acetylgalactosamine galactosyltransferase, retained the same level of activity in these glands. Subsequent to this finding we have obtained an antibody directed to the SDS denatured form of the soluble bovine milk 4 Beta-galactosyltransferase. The antisera shows cross-reactivity with the membrane bound form of the 4 Beta-galactosyltransferase of the rat parotid gland. Isolation of polysomes or size fractionation of mRNA by sucrose gradient, followed by in vitro translation and immune precipitation will allow us to isolate the appropriate mRNA for cloning by making use of viral reverse transcriptase for making cDNA. This cloned probe would allow us to study in detail, genomic organization, expression and regulation of protein glycosylation. Most importantly this probe could then be used to study human galactosyltransferase found on "vector libraries." It is known that carbohydrate structures on cell surface proteins allow them to bind to substrates. Alterations in carbohydrate structure of salivary glycoprotein may change their ability to bind to tooth enamel or other oral surfaces. This altered binding of salivary protein could subsequently alter dental plaque as well as other ionic substances such as Ca+2. Furthermore alterations in saliva play a role in oral disease. Genetic defects in various glycosyltransferases have been shown to lead to storage diseases as well as other types of metabolic illnesses.